Distance and angle measurer.



PATENTED DEC. 31, 190 7.

J. M. KAUFFMANN. DISTANCE AND ANGLE MBASURER.

APPLICATION FILED J'UNEZZ, 1907.

3 SHEETS-SHEET 1.

RS 60., WASHINGTON L c PATENTED mam-s1, 1907 J. M. KAUPFMANN. DISTANCE AND ANGLE MEASURER.

APPLICATION FILED JUNE 22,1907.

3 SHEETS-SHEET 2.

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PATENTED DEC. 31, 1907:.

J. M. KAUFPMANN. DISTANCE AND ANGLE MEASURER.

APPLICATION FILED JUNE 22,1907.-

3 SHEETS-SHEET 3.

nu: uonms PETERS co., WASHINGTON, n. c.

UNITED STATES PATENT OFFICE.

JEAN MICHAEL KAUFFMANN, OF BETTEMBURG, LUXEMBURG.

DISTANCE AND ANGLE MEASURER.

T 0 all whom it may concern:

Be it known that I, JEAN MIcHAEL KAUFF- MANN, geometrician, subject of the Grand Duke of Luxemburg, residing at Bettemburg, in the Grand Dukedom of Luxemburg, have invented new and useful Improvements in a Distance and Angle Measurer, of which the following is a specification.

The invention refers to a distance and angle measurer of the kind in which two mirrors are employed the one of which is rigid the other being movable, and the respective distance is measured by the angular position of the movable mirror, on which a part of the silvering has been removed for the purpose of allowing the observer to look straight through.

The purpose of the present invention is to provide a distance and angle measurer of this kind in which the ray of light is reflected only once.

A further object of the invention is to increase the accuracy of the reading of the angle around which the movable mirror is turned. These purposes are obtained by the two mirrors being arranged in line, and one behind the other, with reference to the line of sight from the eye of the observer, the point, the distance or angle of which is to be measured, lying on the side of the sight line. The accuracy of the reading of the angles is increased by means described in the followlng.

In the accompanying drawing a mode of carrying out the present invention is exemplified, Figure 1 being a plan of the distance and angle measurer; Fig. 2 is a side view: Fig. 3 is a side view with part section through the arrangement for carrying the ocular mirror; Fig. 4 is a plan of this arrangement; Fig. 5 is a side view with part section through the object mirror carrier; Fig. 6 is a plan of the same; Fig. 7 is a plan of an arrangement for reading the angle of the ocular mirror; Fig. 8 is a vertical section through the same; Fig. 9 is a diagram showing the arrangement, and serving to explain its use.

On a base 4., provided with three feet 1, -2- and 3, is adjustably fitted a socket 6, preferably by means of a ball and socket joint 5, in which socket the tube 7 forming the longitudinal axis of the apparatus is fitted. Tube 7- can be fixed in socket 6 by means of set-screws S. On the right hand end of the tube 7 is fitted a socket 9, which can like- Specification of Letters Patent.

Application filed June 22. 1907. Serial No. 380,297.

Patented Dec. 31, 1907.

wise be fixed by means of two set-screws 10. The socket 9 has below a ball and socket joint 1 1* by means of which it can be coupled to the base 4, if necessary or desirable to substitute socket 9 for the socket 6. On the top side of socket 9 is provided a circular disk 12 with a pivot 13 in its center von which swivels a second disk '14:. This disk 14- is provided with two radial arms 15 and 16 the ends of which are shaped as pointers 17 and 18, which slide on the outer, somewhat raised rim 19 of the larger disk 12. The pointers 17, 18 have a bevel at their extreme edge which corresponds with a similar bevel on the edge 19 of disk 12. This bevel has a graduation in whole and half degrees. On the pointers 17, 18, upright edges 20,

2 1 are provided which are suitably sharpened on their top and lie in a line with the zero marks on the pointers. The disk -14- has an outer rim 22 projecting upwards, and encircles with this rim 22 the rim 25- of a third disk 24- swiveling on a set-off 23 of pivot 13. This disk 24 is held in position by a nut 26 screwed on its pivot, but can freely swivel around the same. In the rim 22 of disk 14- is provided a set-screw -27 which penetrates through the rim and by means of which the disks 1 4 and 24 can be rigidly coupled together. A similar set-screw 28 is provided in a lug 29 provided on the large disk 12 and serves to rigidly couple the disk 14: to disk On the inside disk 24 are provided lugs 30 which serve as ripping means to provide for turning of thls disk. In its center this disk 24 has an upwardly proj ecting ring 3 1 encircling the nut 26, on which is screwed a plate -32- which carries on its top a frame 33 serving to receive the mirror -34. This mirror has a center-cross *35 a recess '36 at the top and a circular hole 37 in the center and can be adjusted around a vertical axis by turning the disk -24 to which it is secured. On the left hand end of tube 7 is provided a similar mirror 38, also with a center-cross -3Q but without the recess or hole of mirror 34. The mirror -3 8- is fitted with a plate 40 on the annular projection 41 of a disk 43 swiveling around a pivot 42. the nut 4 1 and has a beveled edge, which corresponds with the beveled edge of the stationary disk 45. The bevel of the stationary disk 45 is graduated, the bevel of the disk 43 has a corresponding pointer not shown. The disk 45- has a socket -46 which is adjustable on tube -7- and can be fixed by means of setscrew 47.

Between the two mirrors 38- and 3 1 and at a given distance from the latter is arranged a short arc 50 by means of the socket 49 fixable by setscrew 18-, said are lying in a plane at right angles to the swiveling axis of mirror 34-, and said axis forming the center of the arc. This are has agraduation the radius of which has been taken in the present ex- 2 7': that one millimeter of the graduation corresponds to an angle of 6 minutes, as the complete circle of the arc has a circumference of 2. r. 360 cm. 2 7r emplification as about 57 cm, so

The arc 50 has a dovetail undercut groove into which fits a corresponding projection 52- of a sliding part 53 corresponding with the arc and serving as divider for the arc 50. The projection -52 has a rack on its lower surface into which engages a pinion 55 fitted with a hand wheel 56 and by means of which the sliding part 53 can be moved on the are 50. The sliding part 53 has on its top a bevel *54- which corresponds to the graduated surface of the arc 50. The bevel 51 has a zero-line and a graduation obtained. by 17 degrees of the graduation on the are being divided into 18 de grees and marked off on both sides of the zero line. The dividing circle of the arc 50 is graduated in half millimeters, so that by means of the divider 17/18 1/36 mm can be read. As one millimeter as said above corresponds to an arc of 6 minutes, the above arrangement allows of reading accurately tens of seconds.

The operation of the arrangement will now be explained in a more detailed manner by reference to Fig. 9. In this figure 34 is the ocular, 38 the object mirror, -50 the arc with the divider 53. A is the eye of the: observer, O the swiveling center of the movable ocular mirror, B the center of the object mirror, -C the object the distance of which is to be ascertained. The point C is to be considered as lying in the crossing point of the rays emanating from B and O As the size of the paper with the drawing does not suffice to show point C in its actual position, a bracket is used, whereby it must-be considered that these rays, which in the This disk is held by 1 following are indicated by -BC- and OC- converge in one pgint, that is C. For measurin the distance of this point the apparatus is Fixed with its longitudinal axis OB pointing at right angles to the direction of the point and adjusted until the image of this point C is seenin the center cross of the object mirror -38. Now the ocular mirror 3 1 is turned until the image reflected by the same over C 0 A appears on the center cross of the mirror and covers the image in the object mirror 38. This covering is possible as mirror 34 has openings 36- and 37 through which the object mirror 38- can be observed. When the two images cover each other the angle between mirror 34- and the basis line OB is, as will be known, equal to exactly half the angle BOC, formed by the line connecting the object with O and the line OB, so that when the former angle is read, the distance of the point C can be calculated in known manner by the given size of the angle OBC- and the length of the basis line OB. The angle, formed by mirror 38 with the line OB is preferably chosen at 45 and fixed so that the angle formed at B by the reflected rays of light is 90, whereby the calculation. is simplified. For certain instances however it may be preferable to have at B- another angle, perhaps an obtuse one. For this purpose the mirror with the disk 43 carrying it can be swiveled around a vertical axis, the degree of the turning being read on the dividing disk 15.

It is evident that if the angle BOC necessary for calculating the distance of point C is found by reading the inclinaan' accuracy is obtained under otherwise equal conditions which is only half as great as if said angle could be read directly. In order to avoid this disadvantage, means are provided according to the present invention, which permit a direct reading of the angle formed by the ray OC. For this purpose serve the edges 20, 2 1 provided on arms 15, 16- on disk -14. One of these edges is moved, after the object images have been made to coincide, on the outer edge or rim 19* until its image also covers the object image in mirror 34 or until the edge appears absolutely vertically below the image of point C in mirror 31. Such position corresponds to the position of edge 21 shown in Fig. 9 by full lines. It is obvious that in such instance edge 21- will be exactly in the direction of the sight line OC so that the angular deviation of the edge 21 from the line OB- also directly indicates the angle, which the line OC forms with the line I OB. This angle can then be easily read :tion of mirror -34 against line OB in degrees and half degrees on the graduation of disk 12. a

In order to obtain a still greater accuracy of reading, the above described arrangement with arc 50- is employed, which will be explained with reference to the diagram Fig. 9. l/Vhen the edge 21- has been adjusted in'the above described manner the whole and half degrees can be read directly on the graduation of disk 12. For also reading the fractions in minutes and seconds, by which the pointer connected to edge 21 deviates from the degrees and half degrees read, the disk 14 carrying arm -16 with the respective pointer is turned back after having been previously rigidly coupled by means of set-screw 27 to disk 24 carrying mirror 34 until the pointer covers exactly a full graduation on the edge or rim l9. This position then corresponds to the position of edge 2 1 shown in Fig. 9 by dotted lines. If now the divider -53 is observed over the image of the edge 2 1- in the center cross of mirror 34 and the divider is adjusted so that its zero line covers exactly with the image of edge 21 in mirror 34 the angle EOB formed by sight line AE with line OB will, as may be seen from Fig. 9 be equal to angle COF around which the pointer has been turned back. This angle can be read from ten to ten seconds by means of the divider on the graduation of arc 50 as described above and must be added to the full and half degrees read on graduation 19, so as to obtain the desired angle BOC- up to tens of seconds.

As the mirrors 34, 38 can be adjusted by means of socket 9 and 46 on the tube 7, the distance of the mirror centers from each other can be optionally adjusted for varying the basis line OB on which the calculation is based. Besides the mirrors may be thus turned around a mutual horizontal axis, that of tube 7 if distance or angles are to be measured which are not in a horizontal level but inclined thereto as may be the case in mountainous districts. A particular advantage of the present invention lies in the fact that by its use the sightray is only once reflected, so that the instrument may be conveniently used even in twilight or dusky weather.

Having now described my invention what I claim and desire to secure by Letters Patent of the United States is:

1. In a distance and angle measurer, the combination of a base, two mirrors attached to said base, one of said mirrors being fixed and the other rotatable relative to said base, the rotatable mirror being provided with means to permit observation therethrough, the reflecting surfaces of both mirrors looking to the same side with respect to the connecting line of the centers of said mirrors,

and means for reading the angle of rotation of said rotatable mirror.

2. In a distance and angle measurer, the combination of a stand, a horizontal tube at tached to said stand, two mirrors attached to said tube, one of said mirrors being fixed and the other rotatable, the rotatable mirror having means to permit observation there through, the reflecting surfaces of both mirrors looking to the same end of the tube, and means for reading the angle of rotation of said rotatable mirror.

3. In a distance and angle measurer a base two mirrors attached to said base, one of said mirrors being rotatably arranged, the rotatable mirror having only a portion thereof silvered, the reflecting surfaces of both mirrors looking to the same side, an index capable of being turned independently of the rotation of the rotatable mirror about the axis of said mirror a graduation for reading the angle of rotation of the rotatable mirror, said index being adjustable on said graduation and having a mark adapted to be seen in the rotatable mirror, as described.

4. In a distance and angle measurer a base, two mirrors attached to said base one of said mirrors being rotatably arranged, the rotatable mirror having only a portion thereof silvered, the reflecting surfaces of both mirrors looking to the same side an index capable of being turned independently of the rotation of said rotatable mirror about the axis of said mirror, a graduated arc concentric to the axis of the rotatable mirror, the diameter of said arc being greater than that of the circle of graduation for said rotatable mirror, said are being provided with a divider slidable along said are and adapted to be viewed through the uncovered part of said rotatable mirror, as described.

5. In a distance and angle measurer a base, two mirrors attached to said base one of said mirrors being rotatably arranged, the rotatable mirror having only a portion thereof silvered, the reflecting surfaces of both mirrors looking to the same side, both mirrors being provided with center crosses, a disk capable of being turned about the axis of the rotatable mirror independently of the rotation of said mirror, indices attached to said disk, upwardly projecting marks on said indices, a graduated disk concentric to said index disk, means for rigidly connecting said index disk with said rotatable mirror and said graduated disk, as described.

6. In a distance and angle measurer a stand, a horizontal tube attached to said stand, two sockets adjustable on said tube and provided on their upper side with graduated disks, each of said disks carrying a mirror being rotatable on pivots of said disks, said pivots being vertically arranged an axis to said tube, both mirrors having their reflecting surfaces looking to the same side and being provided with center crosses, one of said mirrors having an index, sliding on the corresponding graduated disk, the second mirror having a circular hole in the center and a recess at the top and being secured to a circular rotatable disk concentric to said pivot and being rigidly fiXable by means of a set screw to another concentric disk provided with indices slidable on the corresponding graduated disk, said index disk having marks projecting beyond the lower edge of said second mirror and being fixable to said graduated disk by means of a set screw, a graduated arc attached to said tube between said mirrors,:said'graduated are being concentric to the axis of the second mirror and of larger diameter than said graduated disk-and lying in the plane of rotation of said second mirror, said arc being also provided with a veneer slidable on it, as described.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

JEAN MICHAEL 'KAUFFMANN.

Witnesses J. MENNEBURG, XoURE BROsEUR. 

